Silverlight Shared MergedDictionaries

Question

I am using Silverlight 4 and trying to share some common styles (colors, brushes). My take was to put them into a \"Common.xaml\" Resource Dictionary and then use it in all othe

Answer 1

The problem is that silverlight appears to streamline loading of resource dictionaries such that multiple dictionaries can be loading in parallel. As a result when one dictionary has a dependency on another that dependency may not be ready in time.

Since ResourceDictionary doesn't have builtin means to describe inter-dependencies nor an event to indicate when it has loaded the only solution I've been able to come to is to manage the loading of the dictionaries myself.

Here is a function you can add to your App.xaml.cs file to "manually" load a resource dictionary:-

    private void LoadResource(Uri uri)
    {
        var info = Application.GetResourceStream(uri);
        string xaml;
        using (var reader = new StreamReader(info.Stream))
        {
            xaml = reader.ReadToEnd();
        }

        ResourceDictionary result = XamlReader.Load(xaml) as ResourceDictionary;

        if (result != null)
        {
            Resources.MergedDictionaries.Add(result);
        }
    }

Now in the Application_Startup before assigning RootVisual you would use code like:-

    LoadResource(new Uri"Assets/Styles/Common.xaml", UriKind.Relative));
    LoadResource(new Uri("Assets/Styles/TextBoxStyle.xaml", UriKind.Relative));

It isn't going to be as efficient as using the Source property but it will work. If you have many such dictionaries and only few "common" dictionaries that contain shared resources then you could use this technique to load only the "common" dictionaries then use:-

Resource.MergedDictionaries.Add(new ResourceDictionary() {Source = new Uri("Assets/Styles/TextBoxStyle.xaml", UriKind.Relative)});

For the other dictionaries that don't have interdependencies on each other.